The present invention broadly relates to data storage media for use with optical scanning machines, which data storage media are adapted to limit access to information stored thereon. More particularly, the present invention concerns optical disks for use in an optical readout system of a computer to limit continual or repeated unrestricted access to stored data by the optical readout system. A method is also provided for limiting access to data stored in an optical medium environment.
The present invention also relates to a data storage device that provides high data storage capabilities and is easily carried by a user in that the device can be approximately the size of a credit card. In particular, the present invention can be used with both conventional magnetic card swipe readers and optical disk readers. Thus, in one embodiment, the present invention may be viewed as a combination of a typical credit card with a (magnetic or optical) strip that is read via swiping the present invention through a card swipe reader and an optical disk such as a mini compact disc (e.g., DVD).
The computer industry has long been plagued by the illegal misappropriation of software products. The Software Publisher""s Association (SPA), an organization with devotes significant resources to tracking and analyzing piracy problems, has determined that in 1994 alone the personal computer software industry lost in excess of $8 billion due to illegal copying of business application software. The SPA further estimated that virtually half of the business software in use in 1994 was pirated, and this estimate does not include the illegal copying of operating systems, education, entertainment or personal productivity software. The piracy problem is particularly acute in more developed markets such as the United States.
Many approaches have been implemented by software producers in an effort to combat piracy. Some of these approaches include encryption, special data formatting complex installation procedures, and passwords, to name only a few. Unfortunately, end user resistance to these anti-piracy schemes has been high because they are plagued by one or more limitations, such as an inability to xe2x80x9ctry before you buyxe2x80x9d, restrictions on the generation of legitimate back-up copies, and password protection techniques which fail once the password is divulged or discovered. The inability of copy protection schemes to win end-user acceptance has been so extreme that many publishers have simply abandoned the effort, choosing instead to rely on the integrity of their customers to abide by copyright laws.
The misappropriation of software is rampant irrespective of whether the data storage medium is magnetic or optical. Magnetic storage disks are particularly susceptible to piracy. Commercially available magnetic disks, such as the conventional floppy disk, are read/write/erase memory devices in which data is stored in a magnetizable surface layer as discrete patterns of magnetism. Information is stored and retrieved by a read/write head which contains a coil wound around an iron core.
While the magnetic recording medium remains the most popular, there has been a growing trend in recent years to utilize an optical medium environment for the storage and retrieval of data. The reason for this trend is readily apparent. A commercially available magnetic floppy disk is only capable of storing 1.44 Mb of data, whereas an optical CD-ROM of the same size can have a capacity in excess of 600 Mb.
In a typical optical disk for use in a computer""s optical readout system, data is stored as a series of lands and pits. This is accomplished by stamping along spiral tracks on a transparent plastic disk, overlaying this with a reflective coating, and thereafter superimposing a protective layer over this coating. Light from a semi-conductor laser is focused onto either the lands or pits from below and the reflected light impinges upon a photodetector which converts the presence or absence of the pits into a binary electrical signal. Because the focused laser spot is so minute, the amount of information that can be stored onto the surface of the disk is immense. Adjacent tracks need only be spaced apart by approximately 0.6 xcexcm and, hence, 20,000 tracks may be available on a conventional 120 mm diameter (5 inch) optical disk. The electrical signals delivered to the optical readout system correspond to the magnitude of the reflected light which either increases or decreases due to interference and/or diffraction by the preformatted data structures.
In the 1970""s, researchers began attempting to encode information on optical disks with lasers, and the video disk was subsequently developed. In the 1980""s, more sensitive materials that could be encoded with a low power diode laser were developed. These diode lasers, operating at a wavelength of approximately 800 nm, are now universally employed to read audio and computer CD""s. Following the advent of compact disks which are capable of being read with a laser diode, researchers have now endeavored to develop a marketable compact disk upon which data can be recorded by an end user. The benefit of this capability, as discussed above, is that optical laser recording provides a much higher information density than magnetic recording.
Presently, there is a write once and read many times (WORM) compact disk. This compact disk utilizes a dye that irreversibly changes state when exposed to a high power laser diode and maintains this state when read with a low power reading laser. As such, detection of the encoded data by the optical readout system does not affect the encoded data.
It is anticipated that the next generation of optical disks will be capable of being written on, read, erased and rewritten on, etc. many times, similar to a magnetic disk. A photochromic material, or chromophore, is attractive for this purpose. Photochromism is the phenomenon whereby the absorption spectrum of a molecule or crystal changes reversibly when the material is irradiated by light possessing certain wavelengths. Thus, for example, a colorless compound may change its molecular state to a quasi-stable colored state when radiated by ultraviolet (UV) light, yet be returned to the colorless state upon exposure to visible light. Both organic and inorganic materials which exhibit these properties have been known for years.
Recently, photochromic compounds have attracted much attention in the field of optical recording. As discussed in Jun""Etsu Seto, Photochromic Dyes, the photochromic materials initially studied for such an application did not have significant sensitivity in the infrared region near 800 nm, the wavelength region of conventional laser diodes. Seto recognizes, however, that a specific class of photochromic compounds, known as spiropyrans, can be manipulated to exhibit improved sensitivity in the infrared region. Specifically, Seto discusses a class of photochromic spiropyrans with benzothiopyran units in the molecular framework and concludes that the synthesized spirobenzothiopyran is well suited to the requirements of erasable optical recording media for systems using conventional laser diodes.
Another dye of the spiropyran class, having the chemical composition 6-nitro-1xe2x80x23xe2x80x23xe2x80x2-trimethylspiro[2H-1-benzothiopyran-2,2xe2x80x2-indoline], or 6-nitro-1-SBIPS for short, is discussed in Tarkka, Richard U., Talbot, Marc E. , et al. , xe2x80x9cHolographic Storage in a near-ir sensitive photochromic dyexe2x80x9d, Optic Comm. 109, 54-58 (1994). This article discusses the use of 6-nitro-1-S-BIPS for use in the holography field wherein the dye becomes colored when exposed to light having a wavelength of 780 nm. The film returns to a quasiclear state upon exposure to an ultraviolet light source at 337 nm.
It is anticipated, based on these recent developments, that the conventional magnetic disk will eventually become obsolete due to the recent developments in optical storage technology. Concurrent with this anticipated phaseout of magnetic disks will be a need to adequately address the piracy issues which have for so long plagued the software industry so that the illegal misappropriation of proprietary rights can be thwarted. Accordingly, while past research has concentrated on utilizing photochromic materials for the recording of information on compact disks, the present inventors have realized that similar photochromic materials may also be used to protect the compact disk against illegal copying and distribution. In addition, the present inventors have also recognized that certain other photoreactive materials, as well as oxygen reactive materials, may be employed for this purpose. That is, compounds such as these may be used to deny access to a specially coated compact disk beyond one or more authorized uses. That is, such compounds, when applied as a coating on a disk, operate to effectively change its light transmissive properties upon exposure to a low power reading laser, thereby darkening the coating on the disk and rendering data undetectable by an optical readout system. Moreover, the inventors have also recognized other optical media data protection techniques for the present invention that also address the unrestricted duplication of information as discussed hereinabove.
Additionally, the need for individuals to easily carry potential large amounts of personal data is becoming increasingly desirable. For example, it is desirable for individuals to carry with themselves their entire medical history, including x-rays and MRIs. Moreover, detailed financial transaction data regarding items purchased and funds available, as well as lines of credit and credit history, may be desirable for a user to easily carry. However, presently known devices for transporting such large amounts of data do not lend themselves to being carried in, for example, a wallet or purse. That is, there have heretofore been no known, readily available devices for reading and/or writing data to/from portable data storage devices, wherein the data storage devices are capable of being carried in a wallet or purse, and wherein large amounts of data (e.g., 50-100 megabytes or more) may be stored.
Accordingly, it would be advantageous to have portable personal data storage devices that can easily fit in a wallet or purse. In particular, it would be advantageous to have such a device having substantially the dimensions of a credit card. Further, it would be advantageous to have such a device wherein the high data storage capabilities of such a device could be easily read from or written to using substantially conventional data read and/or write devices such as compact disc readers and magnetic card swipe readers.
The need for individuals to easily carry potential large amounts of personal data is becoming increasingly desirable. For example, it is desirable for individuals to carry with themselves their entire medical history, including x-rays and MRIs. Additionally, detailed financial transaction data regarding items purchased and funds available, as well as lines of credit and credit history, may be desirable for a user to easily carry. However, presently known devices for transporting such large amounts of data do not lend themselves to being carried in, for example, a wallet or purse. That is, there have heretofore been no known, readily available devices for reading and/or writing data to/from portable data storage devices, wherein the data storage devices are capable of being carried in a wallet or purse, and wherein large amounts of data (e.g., 50-100 megabytes or more) may be stored.
Accordingly, it would be advantageous to have portable personal data storage devices that can easily fit in a wallet or purse. In particular, it would be advantageous to have such a device having substantially the dimensions of a credit card. Further, it would be advantageous to have such a device wherein the high data storage capabilities of such a device could be easily read from or written to using substantially conventional data read and/or write devices such as compact disc readers and magnetic card swipe readers.
It is an object of the present invention to provide a new and useful optical medium, such as an optical disk, and system therefor which is adapted for use with an optical readout system of, for example, a computer, wherein the readout system includes a light source operative to produce an interrogating beam of light for reading data structures on the optical medium.
Another object of the present invention is to provide such an optical medium which is particularly adapted to prevent unrestricted access to encoded information thereon by an optical readout system, wherein the information may be, for example, graphical data, video data, audio data, text data, and/or a software program.
Another object of the present invention is to use the error detection capabilities of a conventional optical medium reader for: (a) determining a status of an optical medium provided by the present invention, and/or (b) verifying an object or person as authentic. That is, it is an object of the present invention to use the errors detected on the optical medium for (a) and/or (b) above. For example, the total number of errors detected in a predetermined area of the optical medium, the density of the errors detected in a predetermined location of the optical medium, and/or the pattern of errors in a predetermined area of the optical medium provides, according to the present invention, sufficient information for (a) and/or (b) above.
Another object of the present invention is to provide verification or authentication of information provided on or with the novel optical medium of the present invention. For example, the present invention may be used for verifying the authenticity of an optical disk having an audio and/or multimedia presentation thereon. Additionally, when the optical medium of the present invention is incorporated into, for example, a financial transaction card, the card can be verified as authentic.
Another object of the present invention is to provide verification or authentication of a user that is, for example, desirous of making an electronic financial transaction such as on the Internet.
A further object of the present invention is to provide a new and useful optical disk which is relatively easy to manufacture without substantial increases in costs.
Yet another object of the present invention is to provide a methodology of limiting access to information stored on an optical medium for use in a computer""s optical readout system.
Still a further object of at least some embodiments of the present invention is to provide an optical disk which is particularly constructed so that an end user is unaware of the disk copy protection features until after they have been performed.
A first collection of embodiments of the present invention accomplishes these objectives by providing an article of manufacture (e.g., an optical disk) that is adapted to be encoded with data and further adapted so that duplication of the data by an optical scanning machine (i.e., an optical readout system) may be restricted. The article of manufacture comprises a substrate fabricated from a selected material, with a surface thereof provided with the data. A reactive compound is formed as a coating on at least a portion of the substrate surface and the reactive compound operates to change from an optically transparent state to an optically opaque state in response to irradiation for an accumulated duration of time by infrared light having desired characteristics, thereby to prevent light from the optical scanning machine from penetrating the reactive compound and to render the data undetectable by the optical scanning machine.
More particularly, an optical disk is provided which is adapted for use in an optical readout system of a computer wherein the optical readout system includes a light source operative to produce an interrogating beam of light for reading data structures. Broadly, the optical disk according to the first collection of embodiments of the present invention includes an inner layer having an upper surface and a lower surface, with the lower surface thereof encoded with information stored as a plurality of data structures that are readable by the interrogating beam of light. The outer layer is disposed in a confronting relationship with the lower surface, and a film of a reactive compound is superimposed over at least some of these data structures. The reactive compound is selected to be of a type which is operative to change physical characteristics in response to a selected stimulus, thereby to affect readability of the data by the interrogating beam.
Preferably, the optical disk includes a layer of reflective material interposed between the lower surface and the reactive compound. This reactive compound may be supported on a lower surface of the disk""s second layer and have a thickness of approximately 2-5 microns or, alternatively, it may be interposed between the lower surface and the disks outer layer. The lower surface is preferably contoured to include a sequence of pits and lands which define the plurality of data structures, with the reactive compound superimposed over at least some of these pits and lands.
The selected stimulus to which the reactive compound responds is an ambient environment selected to be either visible light, infrared light, light and oxygen, or simply air. Where the stimulus is light alone, the reactive compound may be a photoreactive material and preferably one selected from a spiropyran class of photochromic compounds. One such compound may be 6-nitro-1xe2x80x23xe2x80x23xe2x80x2-trimethylspiro-[2H-1-benzothiopyran-2,2xe2x80x2-indoline], or 6-nitro-1-S-BIPS for short. Such a photochromic compound is operative to change from an optically opaque or darkened condition in response to an interrogating beam wavelength of approximately 780 nanometers (nm) and thereafter return to an optically transparent condition in response to a irradiation by a beam of light having a wavelength of approximately 337 nanometers (nm).
Where the stimulus is a combination of light and oxygen, the reactive compound would therefore be photoreactive with oxygen and preferably operate to change its physical characteristics in response to an interrogating beam of light having a wavelength of approximately 650 nanometers (nm) which is encountered with digital versatile disk (DVD) readers.
Where the environmental stimulus is simply air (more precisely, oxygen), the reactive compound may be one which is operative after an accumulated duration of time to oxidize and alter an optical characteristic thereof. For example, such a reactive compound would change from an optically transparent condition to an optically opaque condition wherein it absorbs light having a wavelength within a desired range. This wavelength could be either 650 nanometers (nm), as discussed above, but may also be in the range of 780 to 820 nanometers (nm). The oxidizing reactive compound may be selected from a group of dyes consisting of methylene blue, brilliant cresyl blue, basic blue 3 and toluidine blue 0.
A methodology of limiting access to data stored on an optical medium such as an optical disk is provided by the first collection of embodiments. Broadly, this methodology comprises the steps of rotating an optical disk in a disk drive at a selected rotational speed, with the optical disk including a substrate layer encoded with information stored thereon as a plurality of readable data structures. A reactive compound is preferably superimposed over at least some of these data structures and this reactive compound operates in an ambient environment containing oxygen to change optical transmission in response to irradiation for an accumulated duration of time by light having a beam wavelength that is within a selected range. An interrogating beam of light having a beam wavelength that is within the selected range is directed toward the substrate layer and through the reactive compound for the accumulated duration of time.
The step of directing the interrogating beam may be accomplished by directing the beam at the substrate layer for a continuous interval of time that is sufficient to cause the change in optical transmission through the optical medium. Alteratively, the interrogating beam may be directed at the substrate layer for a plurality of discrete intervals of time sufficient to cause such change. Where this is the case, it is contemplated that the interrogating beam may be selectively advanced radially across an outermost surface of the optical disk until the beam interacts with the reactive compound for the plurality of discrete intervals of time. The interrogating beam""s wavelength may be approximately 780 nanometers (nm) where a CD-Rom optical disk is utilized, or have a wavelength of approximately 650 nanometers (nm) which is the wavelength employed for digital versatile disks (DVD). Preferably, the interrogating beam also has an intensity of approximately 1 milliwatt (mW) of power, which is typically encountered in conventional optical readers.
In a second collection of embodiments of the present invention, a method and apparatus are provided for prohibiting unrestricted duplication of information on an optical medium such as an optical disk, wherein the user manually affects a physical change to the optical disk during an initial use of the optical disk. For example, the user may activate or perform a predetermined procedure for rendering one or more predetermined areas or locations of the optical disk unreadable or more error prone. This in effect xe2x80x9cmarksxe2x80x9d the optical disk both visually to the user and computationally to a program for accessing information on the optical disk (e.g., graphical data, video data, audio data, text data and/or a software installation program) as having been previously used for accessing the information on the optical disk. Thus, in a subsequent attempt to access the information on the optical disk (e.g., a subsequent attempt to view a multimedia presentation such as a movie, or a subsequent attempt at reinstallation of a software application on the optical disk), it is possible to detect that the information on the optical disk has been previously accessed due to a change in the information on the disk that is able to be read by an optical reader. For example, the optical reader may detect a greater number of read errors than when the optical disk was first accessed for information retrieval.
Alternatively, in other embodiments of the present invention, instead of purposefully creating unreadable portions of the optical disk, a converse method and apparatus may be employed wherein a predetermined portion of the optical disk is initially unreadable and subsequently becomes readable. That is, a mask or covering may be attached to the optical disk during manufacture so that a predetermined portion of information on the optical disk is initially unreadable by an optical reader, but upon initial use of the optical disk, the user physically removes or changes the mask, thereby allowing a sufficient amount of the previously unreadable portion underneath the mask to be read. Accordingly, optical disk accessing software can be performed that detects a state change in the optical disk due to the removing or changing of the mask.
It is a further aspect of at least some embodiments of the present invention that an encoded identifier is provided to a user upon first use of an optical medium of the present invention. Such an encoded identifier is particularly useful for prohibiting unwanted duplication and/or use of commercial software since the identifier is derived from a unique physical change of the optical disk, and, for example, serial numbers of the installation computer. Thus, the encoded identifier, when supplied during a reinstallation attempt and decoded, allows the present invention to determine whether the user is attempting to install the software on a computer different from the original installation. Thus, upon detecting a state change indicating the software has been previously installed, the present invention may restrict various kinds of access to the information on the optical medium. In particular, if the optical disk provides software programs that may be installed on a user""s computer, installations beyond the initial installation may be prohibited if the installation is not on the same computer as the initial installation.
Other collections of embodiments of the present invention are also provided hereinbelow. In particular, collections of embodiments are described relating to verification and/or authentication of financial transaction cards or financial transactions.
Additionally, embodiments of personal data storage cards are provided by the present invention. In particular, a data storage card is provided that includes data stored thereon using a combination of data storage mediums including a magnetic strip, and an optical storage portion (e.g., one of an optical disk or a magneto optical disc). The card of the present invention is sufficiently small (e.g., approximately 2xe2x85x9 inches by 3xe2x85x9c inches so that it can be used as a typical identification/financial transaction card wherein data included on the magnetic strip of the card can be swiped through a conventional magnetic strip reader for reading data from the card. Furthermore, the optical data storage portion of the card is capable of being read by a compact disc reader and/or a DVD reader when the card is rotated on the reader""s optical disc spindle via the spindle penetrating hole in the card. That is the card can be used as a conventional optical disc.